This application relates to devices, techniques and materials related to biofuels.
In general, fossil fuels in modern engines provide incomplete combustion and create adverse heat transfers, particularly in automotive engine applications. In large part, this is because conventional operation of engines provides for homogeneous-charge combustion and allows quenching of fuels undergoing combustion with consequent heat losses to the piston, cylinder walls, and head components along with pollutive emissions. After quenching of combustion, partially burned fuel constituents pass out of the combustion chamber to the exhaust system to cause further efficiency losses and pollution of the atmosphere. In both homogeneous-charge and diesel engine operations, liquid fuel droplets must be evaporated and depolymerized or “cracked” to promote combustion. These processes require heat from the air or from the combustion of other fuel constituents and considerable time for these events to be completed in order to complete the combustion process. About ⅓ of the heat released by combustion is lost through the cooling system of the engine and is dissipated to the environment through the radiator. Engines are designed to open the exhaust valve when the hot combustion gases still have considerable pressure and thus substantial amounts of heat and pressure potential energy is lost through the exhaust system. About ⅓ of the heat released by combustion is lost through the exhaust system of the engine and is dissipated to the environment.
In order to provide for marginal relief from atmospheric pollution, fuel purveyors have promoted more complete combustion of fossil fuels by additions of supplements such as methyl tertiary butyl ether or “MTBE” a compound with the molecular formula C5H12O. However because of groundwater water contamination by MTBE a more recent practice has been to add ethanol a compound with the formula C2H5OH. The concentration of such oxygenated additives has been about 5% to 10% of the total fuel mixture. In practice it has been shown that such additions of oxygen at the carbon to oxygen ratio of 5:1 or 2:1 for a relatively small fraction of all the fuel molecules present in the combustion process helps promote more complete combustion by providing oxygen for oxidation of other fuel constituents. Nevertheless, considerable additional expense is incurred for catalytic reactors for attempts to marginally reduce air pollution from engines using hydrocarbon fuels with additions of ethanol. Such air pollution remains objectionable particularly in congested cities and can cause or exacerbate lung diseases, heart and circulatory problems, corrosion of construction materials and contributes to greenhouse gas accumulation problems.